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A175823
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Numbers n such that gcd(n^2, reverse(n^2)) = n
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0
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1, 9, 297, 513, 783, 999, 1323, 1331, 4961, 10989, 11979, 12969, 14733, 20402, 29088, 89109, 99999, 109989, 122221, 188887, 210789, 218097, 377199, 477773, 483516, 525503, 718189, 1099989, 2128806, 2920819
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OFFSET
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1,2
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LINKS
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EXAMPLE
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297 is in the sequence, because 297^2 = 88209, and reverse(88209)=90288 = 297*304
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MATHEMATICA
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Select[Range[5000000], GCD[FromDigits[Reverse[IntegerDigits[(#)^2 ]]], #^2]==# &]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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